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Question

Use the Rational Roots Theorem to solve for the rational roots

3x4 - 2x3 + 8x2 - 6x - 3 = 0  

Answer
I gather you meant: 3x^4 - 2x^3 + 8x^2 - 6x - 3 = 0
So, the rational root theorem states that *if* there are
rational roots to this polynomila, then it would have to be
of the form (factors of -3)/(factors of 3)
thus, possible roots: x = {-1, 1, -3, 3}/{-1, 1, -3, 3}
or -1, 1, -3, 3, -1/3, or 1/3

You can try each one, and you'll see that x=1 and x=-1/3 are the
only rational roots (the other two are imaginary: -sqrt(3)i, sqrt(3)i).

Abe

Algebra

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Abe Mantell

Expertise

Hello, I am a college professor of mathematics and regularly teach all levels from elementary mathematics through differential equations, and would be happy to assist anyone with such questions!

Experience

Over 15 years teaching at the college level.

Organizations
NCTM, NYSMATYC, AMATYC, MAA, NYSUT, AFT.

Education/Credentials
B.S. in Mathematics from Rensselaer Polytechnic Institute
M.S. (and A.B.D.) in Applied Mathematics from SUNY @ Stony Brook

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